What is Conservation Agriculture (CA)?
CA is a set of soil management practices that minimize the disruption of the soil’s structure, composition and natural biodiversity. Despite high variability in the types of crops grown and specific management regimes, all forms of conservation agriculture share three core principles. These include:
- maintenance of permanent or semi-permanent soil cover (using either a previous crop residue or specifically growing a cover crop for this purpose);
- minimum soil disturbance through tillage (just enough to get the seed into the ground) ;
- regular crop rotations to help combat the various biotic constraints;
- supports soil health and the rich natural ecosystem
CA also uses or promotes where possible or needed various management practices listed below:
- utilization of green manures/cover crops (GMCC’s) to produce the residue cover;
- no burning of crop residues;
- integrated disease and pest management;
- controlled/limited human and mechanical traffic over agricultural soils.
When these CA practices are used by farmers one of the major environmental benefits is reduction in fossil fuel use and greenhouse gas (GHG) emissions. But they also reduce the power/energy needs of farmers who use manual or animal powered systems.
From the Conservation Agriculture Knowledge Portal at Cornell University
Dirt: The Erosion of Civilizations David R. Montgomery, 2012
This is where many people begin their experience with CA
Dirt, soil, call it what you want—it’s everywhere we go. It is the root of our existence, supporting our feet, our farms, our cities. This fascinating yet disquieting book finds, however, that we are running out of dirt, and it’s no laughing matter. An engaging natural and cultural history of soil that sweeps from ancient civilizations to modern times, Dirt: The Erosion of Civilizations explores the compelling idea that we are—and have long been—using up Earth’s soil. Once bare of protective vegetation and exposed to wind and rain, cultivated soils erode bit by bit, slowly enough to be ignored in a single lifetime but fast enough over centuries to limit the lifespan of civilizations. A rich mix of history, archaeology and geology, Dirt traces the role of soil use and abuse in the history of Mesopotamia, Ancient Greece, the Roman Empire, China, European colonialism, Central America, and the American push westward. We see how soil has shaped us and we have shaped soil—as society after society has risen, prospered, and plowed through a natural endowment of fertile dirt. David R. Montgomery sees in the recent rise of organic and no-till farming the hope for a new agricultural revolution that might help us avoid the fate of previous civilizations. From the Preface
- Video presentation on DIRT by David Montgomery: https://m.youtube.com/watch?v=LQ1ALlfMtUk
The Conservation Agriculture Group at Cornell University
This site maintains a very diverse international resource for CA. Academic articles, international groups, monthly news, upcoming conferences, the Two-wheel Tractor Newsletter and much more is available at this knowledge portal/website. It is an excellent first stop for up to date CA resources and news.
This organization and their website has excellent information, including videos, equipment, conference information and presentations as well as links to a very large number of regional CA groups.
Dirt First, a renegade soil scientist is transforming American agriculture, Kristin Ohlson, in Orion Magazine, 2016
In a very accessible way this Orion magazine article by Kristion Ohlson tells the story of the critical importance of soil health,.
Thousands of years of poor farming and ranching practices―and, especially, modern industrial agriculture―have led to the loss of up to 80 percent of carbon from the world’s soils. That carbon is now floating in the atmosphere, and even if we stopped using fossil fuels today, it would continue warming the planet. In The Soil Will Save Us, journalist and bestselling author Kristin Ohlson makes an elegantly argued, passionate case for “our great green hope”―a way in which we can not only heal the land but also turn atmospheric carbon into beneficial soil carbon―and potentially reverse global warming. From the Amazon review: The Soil Will Save Us
Landscapes Transformed: The History of Conservation Tillage and Direct Seeding, edited by C. Wayne Lindwall and Berie Sonntag
Jeff Esdaile’s Two-Wheel Tractor Newsletter
There is a wealth of very creative mechanization for farmers who have access to two wheel drive tractors. The site is hosted by the Cornell Conservation Agriculture website.
Roller/Crimper Designs for Cover Crops Management on Different Farm Scales Using Conservation Practices, Ted S. Kornecki, Agricultural Engineer, USDA, 2014
This is good example of much needed CA equipment being scaled down in size and weight. Test results are presented very clearly.
Here is a fun example of citizen science and a good measure of soil health that children can dig into. One of Earth Link’s first projects was an environmental group for high school students and as one of our activities we sold worms.
Three images of the “Jua Kali Planter” from Earth Links’ coming open source equipment database
Earth Links is working on a database and website for small-holder farmers who need well designed, tested, and very inexpensive tools that can be be construct by local blacksmiths or manufactured regionally. Designs will be available as CAD files, PDFs, photos and videos.